I get a designed web pages from you and I turned it into an html pages and connect it to your data bass and upload it on your server that's the easy explanation about it I use c#, SQL2012 , html ,j query, Ajax, css and java script . and for mechanical engineering (H. V. A. C) I tack from an plan for your project and some information like its location and north direction and hourly work of the place and I made an estimation to air condition load and I do the shop drawing of the plan so it can execute it easily